A group of Chinese tourists caused an uproar inside Vietnam’s Cam Ranh International Airport on Monday after customs officers demanded that they give them tips.The tourists were on their way to a flight back to Sichuan from the coastal resort of Nha Trang in southern Vietnam when they ran into problems at customs. One of the tourists posted an account of the incident on Weibo, claiming that Vietnamese customs officers asked for a 10 yuan tip from each traveler, threatening to seize the passports of any who refused to pay up.Some who did refuse were then asked for more and more money. One man was eventually forced to pay 100 yuan so that he, his wife and their child could get on the plane, the netizen alleges.Predictably this situation led to a confrontation between about 100 Chinese tourists and a dozen Vietnamese officers. In a series of videos that have gone viral on Chinese social media, Chinese tourists can be seen protesting against this latest injustice by using the tried and true tactic of breaking out into the Chinese national anthem. Meanwhile, on the other side, Vietnamese customs officers readied their stun guns.Overall, the incident did not result in much violence. One woman told reporters that officers had struck her husband on the back with a stun gun while he was trying to film the confrontation.Netizens from across China have wrote in, claiming that they were also hassled for tips when returning from Vietnam and other Southeast Asian countries, and arguing that Chinese tourists should no longer visit Vietnam until these issues are resolved.The Chinese consulate in Ho Chi Minh City has confirmed that the incident took place, issuing a statement to say that all Chinese citizens involved have already returned to the mainland and that they have requested an immediate response from the Vietnamese government. So far, nothing from Hanoi.State media reports that already, in just the first four months of this year, 789,500 Chinese tourists have traveled to Vietnam, an increase of 47% from last year. Which all seems like pretty good money for Vietnamese customs officers, blackmailing Chinese tourists leaving the country with luxury items — like lucky pears, brides and lychees, we presume.While extorting travelers seems to have been a fairly common practice in the past for Vietnamese customs, in recent years, various anti-corruption crackdowns have managed to mend the ways of unscrupulous officers, though apparently it hasn’t worked on everyone.Watch video of the incident here: